I didn't know anyone else made a header for the Edelbrock alum head, and how about Merc. changing the bolt pattern so everyone with 525,600,700 would have to buy them from them

Mind Sharing how you pickle them? I'm interested.

What about Hardin Marine Hurricane?

Do not buy the Merc headers; you will pay almost double and not get any better quality than the Gen-X headers. I bought a set of Gen-X headers last year and they were a direct replacement. I only had that boat through the end of the season so can't really comment on longevity of them but they are supposedly better than the original Merc spec CMI's. I have seen one person comment on here about a set of Gen-X's developing leaks pretty early so buyer beware. When I was at the Miami boat show this past February, I got a look at the Hardin Marine Hurricane Lites for 525's and they looked great and seemed very solid but noone seems to know much about them. If I were replacing my headers now, it would be a toss up between the Gen-X's and the Hardins. No matter which you get, the reality is you to need to take care of them. 1) Do your best not to let them overheat. 2) drain them after they cool.. 3) pressure test at regular intervals..

I pressure test every 10-15 hours with this...

[ATTACH=CONFIG]528237[/ATTACH]

The tester consists of a pressure regulator, 1/4" ball valve and pressure gauge and a bunch of fittings to get it all together. First, I block off the water inlet and outlet with 1" rubber furniture stoppers and hose clamps. I hook one end of the tester to an air compressor and the other end to the 3/4" fitting on the header. Then I open the small blue drain plug and let some air in to purge any remaining water in the headers so they're empty for the test. Next, I set the regulator to 60 psi, open the valve to fill the header with air, close the valve, then monitor the gauge to see if there is any loss in pressure. It really works great and will tell you if you have any leaks before they really bite you. It's easy, safe and you can do it pretty regularly without taking the headers off. It's basically a leakdown test for your headers..

That page says:
So...you have to drill and tap your Merc/Eddy heads ?

2 gallons of antifreeze with 3 gallons of water in a 5 gallon pickle bucket. Run motors till hot, switch hose to draw out of pickle bucket, pull through until the buckets almost empty and shut down. I drain off whats sitting in the headers and the blocks and the heat makes a nice vapor that coats everything. Works great. I do this if the boats going to sit more than a few weeks and for sure when laying up over the winter.

Salt water left behind in a hot motor is probably the single worse thing you can do to your headers other than overheating them.

Apparently, I knew that was the case before but saw the advertisement last week as "525 replacements" and assumed they changed the bolt pattern. Apparently all they changed was the marketing.

yes,4 holes have to be drilled and tapped,,search here,gaskets have been compared.

Gotta side with Tank on this one. Their name is on the headers, it's their product, otherwise it should have been built for Merc with the Merc name on the pipes if CMI had issues with the design. That design cost many people big bucks to fix, time out of the boat, and a large measure of hassle. It's not like it's a broken $50 part, this is serious stuff. And regarding their squabbles with Merc, they shouldn't have to drag the customer into their design issues with their client, that should have been settled between the two parties and the problems worked out before shipping a questionable product.

[http://www.xs-power.com/other-specialty-marine-4.htm TRY THESE PEOPLE I HAVE HAD EMAILED THEM BACK AND FORTH AND THEY WILL BUILD ANYTHING YOU DESIRE

About 2 1/2yrs ago Dana Marine stated that they were coming out with a conversion bracket for the bolt pattern for $325 per engine. You bolt on the bracket to your 525, the bracket had a standard block bolt pattern that would allow you to mount any header to it. Not sure if it they ever came out with the product or not, but it would definitely be worth the call.

Dana Marine is currently being transitioned to new owner and has had horrendous customer service for a very long time. I wouldn't buy anything this important from them... Hopefully the new owner can straighten them out..

Man I sure hope my experience is different. We sent in a pair that were leaking after very low hours of usage. There are some inconsistencies so far on service, communication and when/if they are leaving the facility. Fingers crossed. :-)

I am in the process of gathering parts to put together a 540 and exhaust is the first thing on my list. I was browsing through the classifieds and something jumped out to me. Why is is that the small block exhaust is so much cheaper? example http://www.offshoreonly.com/classifi...o51050-en.html Aren't they pretty much the same size and use the same material. Here is an add for what I believe is the same exhaust only for a big block. (both cmi e-top) http://www.offshoreonly.com/classifi...o31966-en.html

Why is their such a price difference?? My only conclusion is that the big blocks are much more prevalent in powerboats so why not do a little price gouging. The same also holds true for the high performance manifolds as well.

all i can say is yup!! talk to these guys xs-power.com i just ordered a stainless y pipe for my truck i am am looking forward to see how it looks. they were half of what summit racing is charging for the magnaflow y pipe. if it is marine related it is going to be marked up.

Very, very small group of SBC boaters who will even spend 2k on exhaust. Let alone, even buy a performance exhaust. For SBC's, There is cheaper alternatives for same power.

I just got the new Hardin Marine headers for the 525's and they sure look great
they are heaver than the cmi's ( but i take that as a good thing) i am done buying cmi's

So am I just extremely lucky or what? 2005 525s with no header issues whatsoever. Boat is 100% freshwater use now since I bought it at 18 mos of age. It had been 100% saltwater use by the original owner for that first year and a half. At 315 hours should you just "replace" headers or wait for a failure? No I have not pressure checked them, not sure exactly how.

Second question is what are the brands that bolt right up? Not interested in an adapter.
Thanks, Andy

if you wait for the failure then your going to be buying a motor and headers , the 525 is a great motor and you can get a lot of hours out of them. at 300 hrs you should be changing the valve springs get new headers and be good for another 300 hrs
you are lucky to have gone this long

the hardin marine headers are a replacement

at 300 hours, you should definitely be doing valve springs and also consider rocker arms. and H20 is right.. if you wait until your headers fail to check, it will be too late.. ask me how I know..

An easy (and safe) way to pressure check the headers while they're still on the boat is with compressed air. You can use a leakdown tester or make a homemade one consisting of a pressure regulator, 1/4" ball valve and pressure gauge and a bunch of fittings to get it all together. First, block off the water inlet and outlet with 1" rubber furniture stoppers and hose clamps. Then hook one end of the tester to an air compressor and the other end to the 3/4" fitting on the header. Then open the small blue drain plug and let some air in to purge any remaining water in the headers so they're empty for the test. Next, set the regulator to 60 psi, open the valve to fill the header with air, close the valve, then monitor the gauge to see if there is any loss in pressure. It really works great and will tell you if you have any leaks before they really bite you. It's easy, safe and you can do it pretty regularly without taking the headers off. Here's what mine looks like.

[ATTACH=CONFIG]528457[/ATTACH]

They are very expensive I think because of the materials being used. If you are out of budget stay away from those mentioned brand look for after market that the price is half.

Neat little device! I am going to do that!

LOL, Funny

My company produces motorcycle exhausts, we use various grades of titanium, carbon fiber, carbon and stainless steel in the different applications and models we make. After buying our boat with the CMI exhaust and reading about the experiences I looked in depth at creating something along the lines of CMI. At the end of the day, producing a CMI like exhaust would have been a substantial up front investment and not being in the Marine industry a large gamble for my company. The margin would have been OK and pricing would have ended up slightly under CMI. So not a smart business decision for us if we went into production. The reason automotive headers are so much less expensive is demand, supplier competition and shear production volume.